Surprising facts about sex

We all do it, but do we know exactly what's going on?

By By Andrea Waguespack

Photo: Getty Images

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Take a numberA study found that millennials are having less pre-marital sex partners than previous generations, with an average of eight partners compared to the eleven that Baby Boomers and Gen X-ers were found to have had.

Take a number
A study found that millennials are having less pre-marital sex partners than previous generations, with an average of eight partners compared to the eleven that Baby Boomers and Gen X-ers were ... more

Take a number A study found that millennials are having less... Photo-7935865.77817 - Houston Chronicle

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Sizing things upA study found that the average length of an erect penis is 5.16 inches and 3.6 inches when flaccid. The study surveyed 15,521 men from across the world ages 16-91.

Sizing things up
A study found that the average length of an erect penis is 5.16 inches and 3.6 inches when flaccid. The study surveyed 15,521 men from across the world ages 16-91.

Sizing things up A study found that the average length of an... Photo-7612977.77817 - Houston Chronicle

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50 Shades of PornPornography website Pornhub released data that found the number of searches for BDSM porn increased after the release of "50 Shades of Grey," especially in women. The site saw a 30% increase in the number of men who searched for "BDSM" porn, while women saw an 186% increase. less

50 Shades of Porn
Pornography website Pornhub released data that found the number of searches for BDSM porn increased after the release of "50 Shades of Grey," especially in women. The site saw a 30% increase in ... more

In certain situations, sex can turn into a humiliating ordeal, and there's probably nothing worse than a trip to the ER because the two of you are stuck together. That's what happened to this couple on vacation in Porto San Georgio, Italy. The Local reports that the pair experienced an uncomfortable vacuum effect after getting frisky in the ocean, and the woman had to have a hormonal injection at the ER.

Bike your way to better sexOne study found that those who bike to work claim to have better sex lives. 89 percent of bikers reported that the time on the pavement allows for the day's stresses tomelt away, leading to a better mood, while 66 percent said their relationships improved. 39 percent of the cyclists also said the exercise gives them more energy in the bedroom. Ride on. less

Bike your way to better sex One study found that those who bike... Photo-6820678.77817 - Houston Chronicle

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Can sex make us smarter? Maybe. Researchers found that the keys to keeping an aging brain from getting atrophied are not just brain games, but naughty bedroom games. (If this is the case, then Einstein must have been a freak in the sheets.) less

Can sex make us smarter?
Maybe. Researchers found that the keys to keeping an aging brain from getting atrophied are not just brain games, but naughty bedroom games. (If this is the case, then Einstein must ... more

Photo: Joselito Briones, Getty

Can sex make us smarter? Maybe. Researchers found that the keys... Photo-2855448.77817 - Houston Chronicle

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Letting go The amygdala, which is the part of the brain that
triggers fear and anxiety, shuts down when a woman has an orgasm. This finding
helps to confirm the idea that women cannot enjoy sex unless they are relaxed. less

Letting go The amygdala, which is the part of the brain that triggers fear and anxiety, shuts down when a woman has an orgasm. This finding helps to confirm the idea that women cannot enjoy sex unless they ... more

Photo: Fotolia.com

Letting go The amygdala, which is the part of the brain... Photo-4124403.77817 - Houston Chronicle

The researchers theorize that larger hips mean a less traumatic birthing experience for these women, so they don't shy away from the horizontal tango. less

Hips don't lie
Large hips could affect more than what size jeans you buy. Researchers claim that women who have large hips (measuring in at 14.2 inches or more) are more likely to have a higher number of sexual ... more

Hips don't lie Large hips could affect more than what size... Photo-6218992.77817 - Houston Chronicle

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Brain gamesGood sex triggers the same part of the brain that's associated with falling in love, according to one study.

Brain games
Good sex triggers the same part of the brain that's associated with falling in love, according to one study.

Photo: Yuri Arcurs, Dreamstime.com

Brain games Good sex triggers the same part of the brain... Photo-4104270.77817 - Houston Chronicle

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This is your brain on pornOne study found that men who regularly view porn could be shrinking their brains and dulling their sex lives. Though, to be fair, the study has yet to determine if the naughty hobby is causing this, or if people who already have these traits tend to flock towards porn. less

Contagious pregnancies?Researchers now claim that getting pregnant could have a domino effect. Scientists found that when one woman gets pregnant, her long-time pals (usually former high school classmates) will ... more

Hair down thereKeeping your bikini area neat and tidy could be doing more harm than good. Recent studies indicate that shaving could lead to the spread of sexually transmitted infections, since shaving can disrupt the skin membranes located in the pubic area and allow for bacteria to make its way in. less

Hair down there
Keeping your bikini area neat and tidy could be doing more harm than good. Recent studies indicate that shaving could lead to the spread of sexually transmitted infections, since shaving can ... more

Photo: SMILEY N. POOL, Getty

Hair down there Keeping your bikini area neat and tidy could be... Photo-4311416.77817 - Houston Chronicle

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Burn, baby, burn!Men burn 4.2 calories a minute while women burn
3.1 calories a minute during sex, according to one study.

Burn, baby, burn!
Men burn 4.2 calories a minute while women burn 3.1 calories a minute during sex, according to one study.

Cancer ConcernsA study found that men who ejaculate at
least 21 times a month were less likely to get prostate cancer.

Cancer ConcernsA study found that men who ejaculate at least 21 times a month were less likely to get prostate cancer.

Photo: Getty Images

Cancer Concerns A study found that men who ejaculate at
least... Photo-4124409.77817 - Houston Chronicle

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A gut feelingA study done at the Arkansas Children's Research Institute found that chlamydia can still live inside a woman's gut, even if she's taken antibiotics to get rid of the genital infection. That means she's more at risk for reinfection. (The study also no-doubt brings good news to partners who've been wrongfully accused of passing the infection to their coitus companions.) less